Deep sleep is a pattern grounded in the perception that nothing exists. Deep sleep allows us to withdraw from conscious awareness.
1.11 anubhuta-visayasampramosah smrtih anu-bhuta - experienced visaya - object (of sensory experience); matters of enjoyment or experience a-sampramosah - non-theft; not being-stolen; not being lost smrtih - memory; remembrance
Remembering is the retention of experiences. Memory is when a previous experience returns to conscious awareness.
1.12 abhyasa-vairagyabhyam tan-nirodhah abhyasa - personal application/practice vairagyabhyam - non-attachment tad - (of) those nirodhah - cessation; dissolution; restraint; suppression; control
Both practice and non reaction are required to still the patterning of consciousness. Consciousness is elevated by Abhyasa (Devoted Practice) and Vairagya (Remembering the Self).